By default, WooCommerce does not redirect to admin. We have measures in place to prevent customers from seeing the admin bar and going to wp-admin.
Your first comment was about being redirected to “/my-account/”, so Mike gave you code to stop users from being redirected to the my account page. Now you don’t want them redirected to wp-admin? So where do you want the redirect? It’s either My Account or wp-admin.
Only customer/users should be redirect to the My Account page when trying to access wp-admin though, administrators and shop managers should still be able to access wp-admin. If that isn’t working correctly, then you have a theme or plugin conflict.
Try temporarily switching back to the WordPress Twenty Sixteen Theme, or Storefront, and disable all plugins except for WooCommerce. If that resolves the issue, then slowly re-enable features until you find the one that’s causing the conflict.